The value of any book depends upon its potential usefulness to the reader.

Sure, but only so far as it presents a concept or premise that you've not considered, or not considered in the way suggested. Most of the Church of Satan's published work is valuable in this way, once you ignore the repetition, but the real gems are in how the books relate to one another.

For example:

In "To: All Doomsayers... & Assorted Tremblers" (Satan Speaks!), Anton LaVey covers a lot of interrelated points; but one of his key themes is that Satanism is interesting, so long as you don't talk about actual Satanism. It was used as filler to scare people, but the truth wasn't worth airing because it was really only designed to reinforce extant beliefs about Devil worship.

Satanism, as we understand it, was never the point.

Time moved on, information became more freely available, and the Aeon of Horus started to really take hold. Rebellion became more commonplace and, suddenly, people weren't quite so frightened by what the media had told it Satanism was. The funny thing is that, were the masses introduced to Satanism properly, it could have undone a lot of the social exclusion and angst that was felt by people who were now proving to be such a nuisance.

The subject is then picked up, though not directly, by Peter Gilmore in "Victors and Victims" (The Satanic Scriptures). In his discussion about Columbine, he muses that Satanism could have actually prevented the Columbine massacre by providing an out for Dylan Klebold and Eric Harris. Smart kids with a bright future were treated to the social exclusion of a typical high school and chose oblivion rather than conformity to a standard they despised. Had they been introduced to Satanism properly, perhaps they'd have appreciated that their talents were worth more than what their classmates declared them to be.

Sadly, thirteen people paid for the oversight with their lives.

James Sass then picks up the idea of damaging group exclusion, caused by the social or physical coercion mentioned by Gilmore, in his essay "On Real Horror Films" (Essays in Satanism). He goes on to describe the alpha-untermensch that populate most social climes and the detrimental impact they can have.

The overall message to distil is that Satanism is so badly misunderstood by mainstream commentators, that they've actually caused damage by presenting it so haphazardly. Conversely, were it to be treated accurately, those who fall into the group that is excluded socially or physically may well find an "outsider" religion that suits their personalities and talents. They'd be given an opportunity to thrive, rather than resort to spraying bullets around.

Now-

Individually, all of these things have valuable lessons to learn. But taken as a group (and there are other articles one could add), you can see how the Satanic strain of thought has evolved into a clear message that spans three authors and several decades, without self-congratulation or contradiction from the source. It's the logical and persuasive development of a concept that has something new to add each time its revisited.

This is what makes those works so much more valuable than, say, Michael Rose's Infernalia. That book angrily repeats itself throughout, makes blunt assertions that are often so wrong as to be incoherent, and introduces no new thinking to the Satanic canon.

It's not even charmingly written.

So while it's accurate to say that one diamond idea can be valuable, even if you need to wade through lots of rough to find it, that's a horribly inefficient way of doing anything. Earlier books in my list present all the same conclusions that Rose does, and they do so much more thoughtfully and with much less immature gibbering to fight through.

Time is precious; our most precious resource, actually. The published work of Michael Rose just wastes so much of it.